diff --git a/types/animation.d.ts b/types/animation.d.ts
index 6fb372c..7d410ab 100644
--- a/types/animation.d.ts
+++ b/types/animation.d.ts
@@ -25,7 +25,7 @@ declare class AnimationHandle implements IAnimation {
 }
 
 export class CompositeAnimation implements IAnimation {
-  readonly handles: Set<AnimationHandle>
+  private handles: Set<AnimationHandle>
 
   constructor()